Corwin, E. S. (1957). The president office and powers 1787-1957: History analysis of practice and opinion (4th ed.). NewYork university press.
Dyfyniad Arddull ChicagoCorwin, Edward S. The President Office and Powers 1787-1957: History Analysis of Practice and Opinion. 4th ed. NewYork: NewYork university press, 1957.
Dyfyniad MLACorwin, Edward S. The President Office and Powers 1787-1957: History Analysis of Practice and Opinion. 4th ed. NewYork university press, 1957.
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